Digital devices can communicate over one or more networks. Devices can be connected to a local network, such as a home network, which is connected to a broader network such as the Internet. Once connected to a network, either through wireless or wireline connections, a device can use one or more protocols to publish a service provided by the device or a device can use one or more protocols to discover a service provided by another device. Various examples of protocols for device and/or service discovery include Universal Plug and Play (UPnP), Digital Living Network Alliance (DLNA), Bonjour, Home Network Administration Protocol (HNAP), Web Services Dynamic Discovery (WS-Discovery), Address Resolution Protocol (ARP), and Domain Name System (DNS) based protocols such as DNS-Based Service Discovery (DNS-SD) or multicast DNS (mDNS).
Some devices, for example, can use an mDNS service to publish and discover services, e.g., printing, media, file sharing, on the same local multicast network. For example, a printer can publish its printing service via mDNS using a multicast data packet. Other devices receiving the multicast data packet can discover the printing service and make the printing service available to local applications such as a word processor. In another example, a media hub can publish its media service via mDNS. Other devices can discover the media service and start receiving content from the media hub. Further, wireless devices such as cellphones, smartphones, or tablets can include an mDNS service process to publish or discover services on the same local wireless multicast network.